In a piston compressor, the reciprocating piston comprises a piston body having a piston head, a piston skirt with piston skirt walls and preferably pin bosses for receiving a gudgeon pin. At least two, preferably three, piston rings, can be introduced into encircling ring grooves in the piston body, of which at least the piston ring closer to the piston head is a compression ring and at least one piston ring, preferably the piston ring closest to the piston skirt, is an oil control ring. Lands are provided on the piston body between each pair of ring grooves and between the piston head and the ring groove arranged closest to the piston head, and on that side of the ring groove arranged closest to the piston skirt that faces away from the other ring groove or grooves.
In the case of a reciprocating piston compressor of the general type under consideration, there may be an unpleasant or toxic discharge of oil into the air. This discharged oil, which is carried in the air, can cause contamination of the systems supplied with this air or even of other, downstream systems, which can lead to problems that can be rectified only with great difficulty in servicing terms, and which can shorten the life of the systems. Also, this contaminated air may cause increased environmental pollution.